ABSTRACT
Objective: To study whether cerebrospinal fluid (CSF) analysis may serve as a diagnostic test for the screening of epilepsy in sporadic prodromal Alzheimer's disease (AD). Methods: A total of 29 patients with epileptic prodromal sporadic AD patients (epADs) were included and were retrospectively compared with 38 non-epileptic prodromal AD patients (nepADs) for demographics, clinical features, Mini-Mental Status Examination (MMSE) results, CSF biomarkers, and electro-radiological features. Results: Our study did not show any significant differences in CSF biomarkers regarding neurodegeneration, albumin levels, and inflammation between epADs and nepADs. The epADs were significantly older at diagnosis (p = 0.001), more hypertensive (p = 0.01), and displayed larger white matter hyperintensities on brain magnetic resonance imaging (MRI; p = 0.05). There was a significant correlation between the CSF Aß-42 and Aß-40 levels with interictal epileptiform discharges and delta slowing on EEGs recordings, respectively (p = 0.03). Conclusions: Our study suggests that CSF may not serve as a surrogate marker of epilepsy in prodromal AD and cannot circumvent the operator-dependent and time-consuming interpretation of EEG recordings. In humans, AD-related epileptogenesis appears to involve the Aß peptides but likely also additional non-amyloid factors such as small-vessel disease (i.e., white matter hyperintensities).
ABSTRACT
This review provides a clinically grounded description of the links between epilepsy and early common neurodegenerative diseases (i.e. Alzheimer's disease, Lewy body disease, vascular cognitive impairment, fronto-temporal lobar degeneration). It shows that epilepsy does not only concern demented patients displaying convulsive seizures (whether focal or generalized) and obvious atrophy on brain imaging. On the contrary, unprovoked seizures and epilepsy - commonly involving the temporal lobe - are now reported at the prodromal stages of these diseases, when cognitive complaints are mild or even minimal and brain imaging inconstantly abnormal. Thus epilepsy must be considered as a part of the phenotypic spectrum at any stages of the neurodegenerative diseases. This must be kept in mind in everyday practice, and when defining these diseases with clinic-biological criteria. Such entanglement also explains the growing prevalence of elderly epileptic subjects and the need of a close collaboration between geriatricians, cognitivists and epileptologists.
